/* @flow */

import { updateListeners } from "core/vdom/helpers/update-listeners";

let target: any;

function createOnceHandler(event, handler, capture) {
  const _target = target; // save current target element in closure
  return function onceHandler() {
    const res = handler.apply(null, arguments);
    if (res !== null) {
      remove(event, onceHandler, capture, _target);
    }
  };
}

function add(
  event: string,
  handler: Function,
  capture: boolean,
  passive?: boolean,
  params?: Array<any>
) {
  if (capture) {
    console.log("Weex do not support event in bubble phase.");
    return;
  }
  target.addEvent(event, handler, params);
}

function remove(event: string, handler: any, capture: any, _target?: any) {
  (_target || target).removeEvent(event);
}

function updateDOMListeners(oldVnode: VNodeWithData, vnode: VNodeWithData) {
  debugger;
  if (!oldVnode.data.on && !vnode.data.on) {
    return;
  }
  const on = vnode.data.on || {};
  const oldOn = oldVnode.data.on || {};
  target = vnode.elm;
  updateListeners(on, oldOn, add, remove, createOnceHandler, vnode.context);
  target = undefined;
}

export default {
  create: updateDOMListeners,
  update: updateDOMListeners,
};
